When the Boston Bruins fired Claude Julien in February, Joel Quenneville took over as the longest-serving NHL head coach. Hired in October 2008, Quenneville enters his 10th season with the Chicago Blackhawks amid a continuously rotating cast of coaching peers. Seven teams hired new coaches this offseason, including the first head coach in the history of the league's 31st franchise, the Vegas Golden Knights. That doesn't include the coaches who took over at some point last season, including Julien (Montreal), Mike Yeo (St.